Counting coils does not fully describe a directional valve's behavior. Spring return, spring centering and detent arrangements determine what happens when a command disappears.

Read the complete symbol

A single-solenoid valve often returns to a defined position by a spring. A double-solenoid assembly may be spring-centered or use another positioning arrangement. Confirm the exact number of positions and the return mechanism instead of assuming two coils mean the valve stays where it was.

Review electrical commands

The controller must manage the outputs according to the valve and machine design. Simultaneous coil energization may be prohibited or produce undefined behavior for a particular assembly. Use the specified interlocking and fault-detection strategy.

Check the machine consequence

Translate every valve state into actuator movement, stopping or floating. Include a lost wire, removed enable signal and total power loss. Replacement acceptance should verify these states with an approved procedure, not merely confirm that the actuator moves in both directions.

Practical checklist

• Record spring and detent details with the spool symbol.
• Confirm controller output interlocks.
• Define the required response when either command is removed.

Discuss your application

Explore related hydraulic products, or send JIUDING your model code and application details. Include the circuit drawing and the operating conditions relevant to the checks above so the required configuration can be reviewed.

Cover image: AI-generated editorial illustration, not a model-specific product drawing or a photograph of a JIUDING facility.